Abstract A generalized film model is used to describe isothermal reactive gas absorption without limitation on the reaction regime. The model is applied to analyze the effect of the liquid phase, bulk-side, reaction on gas absorption accompanied by a general ( m,n)-th-order reaction involving a volatile liquid reactant. A computational analysis is performed in order to examine criteria given in the literature for the condition(s) under which the contribution of the bulk reaction can be significant. It is shown that the Hatta number is not the only indicator by which the importance of this contribution should be assessed. Other parameters reflecting reactor type, operating conditions, reaction orders, and extent of liquid mixing are shown to play an important role in determining the significance of the bulk-liquid reaction in the slow- and moderately fast-reaction regimes.